How do I setup SNMPd on CentOS 7?

To setup SNMP daemon firstly install the required packages.

yum install net-snmp net-snmp-devel net-snmp-libs net-snmp-utils

Then edit the main configuration file

vi /etc/snmp/snmpd.conf

Find the line starting with "com2sec" and change the community from "public" to your secret v2c community name. If you also wish to use version v1 you can also add a line "rocommunity SECRET_COMMUNITY" at the end of the file.

You will then need to start the service

service snmpd start

And configure it to start automatically

systemctl enable snmpd

The SNMP daemon should now be running which can be used to monitor the server via Cacti etc.